Addressing fruit allergen detection gaps: A validated LC-MS/MS method for eight allergenic fruits in foods

Fruit allergies are an increasingly concerning food safety issue, yet analytical methods for simultaneous detection of multiple fruit allergens remain limited. This study developed a multiplex LC-MS/MS method for quantifying allergens from eight common fruits (kiwi, pineapple, mango, banana, apple, strawberry, peach, cherry) in juices and yogurts. Signature peptides from major allergens including Act d 1, Man i 1, and Mus a 5 were identified via LC-HRMS screening. Sample preparation was optimized using SP3 magnetic bead enrichment, addressing low protein content challenges in fruit matrices. The method achieved limits of quantification of 5.0-10.0 mg/kg with recoveries of 68.7-86.8% in juice and 68.2-84.5% in yogurt matrices. Validation demonstrated excellent specificity, linearity (R² ≥ 0.994), and precision (RSD ≤ 12.7%). Analysis of 35 commercial samples revealed undeclared allergens in 31% of products, with high concentrations in mixed-fruit products. This robust method addresses critical gaps in fruit allergen surveillance and supports enhanced food safety management.